Well, what's a requirement is that no money be spent without congressional authorization and appropriation. That's not a mandate on Congress to spend, and so again, they simply have to agree to how much they're spending, and on what. Our society is diverse enough, and our spending is massive enough, that i've gotten beyond the ability to get too passionate about budget policy.
Perhaps the real solution here is to go back to the days when agency authorizations and appropriations were passed individually rather than as a single massive reconciliation. At least that way, the silly ideological and policy firefights could be contained.